


Accidental Mass Adoption

by Lunahras



Category: Undertale (Video Game)
Genre: Angst, Gen, Misgendering, SO MUCH FLUFF, but also fluff, gotta get through the angst first tho, have parental skelebros, its a thing that needs to exist, so many oc's but hey thats what youre here for, this has been bothering me for ages so now i gotta, you will choke on it its that much
Language: English
Status: In-Progress
Published: 2018-12-22
Updated: 2019-01-11
Packaged: 2019-09-24 12:59:18
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 3
Words: 3,630
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17101031
Author URL: https://archiveofourown.org/users/Lunahras/pseuds/Lunahras
Summary: Turns out, humans can be pretty shitty to their own too. Somehow this really doesn't come as much of a surprise to Sans. But, well.... they really can't just leave children to struggle alone.Well at least Papyrus is having the time of his life





	1. Sans Is A Nonbeliever, We Totally Have A Plan

**Author's Note:**

  * For [Rehlia](https://archiveofourown.org/users/Rehlia/gifts).



> hi and welcome to my new de-stressing project cause my last one developped plot that i actually gotta think about now. expect sporadic updates and varying chapter lengths
> 
> WARNING: this story will deal with a heck of a lot of sensitive topics ranging from discrimination to abuse to homelessness and so on. my kids go through some shit alright?? ye've been warned
> 
> edit: i FHOrgto th e suMMAriiy

On a bright and sunny afternoon, on a route usually taken by one single child at this time of the day, two children walked side by side.

“Frisk, I don't know if this is a good idea.... maybe I should just go b-ba-” he stuttered to a stop as his lips were mushed back by an unforgiving finger. Frisk looked stern as they firmly reiterated that no, he wasn't going back to his mom'ss place tonight. Not ever again if they got their way...

“But- but I can't- Frisk I don't know if you've noticed but your mom is _scary_.” Sam insisted, “And it's really not that bad, I'm used to i-”

Frisk shook their head vehemently. No way! Absolutely no way they were going to just  _leave him_ to deal with- They took a deep, calming breath and consciously unclenched their fists at Sam's pained expression, an apology offered before they even really thought about it. And their mom wasn't scary! She was just.... strict.

Sam snorted and offered them a wry smile, the first one today. Frisk felt smugly satisfied about that. “She  _is_ scary! When she gets mad at someone she gets this face-!” His attempt at imitating Toriel's admittedly intimidating expression of utter disapproval were lackluster at best and got a giggle out of Frisk, but, yeah, ok, they could see his point. They guessed only knowing her as a teacher, the other kids at school probably didn't have the cuddliest impression of their mom.

And well... she was really,  _really_ busy. Like, unhealthy levels of busy. Even after charming her way through a job interview at the local elementary she'd never actually stopped (reluctantly) helping Asgore out with the legal and societal nightmare that was monster integration. Toriel tried to hide her exhaustion, of course, but Frisk had always been much too perceptive. Adding another child with this kind of tangled up issue onto the mix.... it probably wasn't the brightest idea.

Frisk squeezed his hand reassuringly as they walked, but didn't say anything. Letting Sam go back wasn't an option on their book, but if he couldn't stay with them, then whom? Undyne and Alphys??

….No. They loved those two, but... no. That could go wrong real quick-like. Asgore? Well, he had a full schedule trying to get his people situated, integrated and safe so.... nope. But who else was caring and friendly enough and wasn't perma-stressed? The only person that came to mind for that description was-

….oh.

Oh, yes. That could work.

Their steps quickened just a tad as a smile stretched across their face, a spark of mischief in their eyes.

Sam almost stumbled in his hurry to keep up, “F-frisk! What-” Frisk flashed him a blinding smile. They knew exactly where to bring him now. Sam's brow furrowed in confusion. “What are you sayiiiiwaaaaahhh!!!” He yelped when Frisk just tugged him along and started borderline running, “Frisk, wait-!”

They tried very hard to keep their balance even as mirth shook their whole body. Of course, Sam caught on and, with the beginnings of a smirk, shoved them with his shoulder. He didn't, however, account for the fact that he was still holding their hand and thus got dragged along in their mad, stuttering scramble to get their feet under them before they could fall.

It made for a very comical sight as the two children entangled their legs in an ultimately futile attempt to stay upright and eventually fell onto the unforgiving concrete of the sidewalk.

“Ow.” Sam managed to get out and Frisk groaned right alongside him. They stood up and took stock of this severe situation: a scraped knee, and somewhat scraped elbow on Sam and generally scuffed clothes. Could be worse, they shrugged and helped the boy up. They were almost there, no time for dawdling!

Sam sputtered as they walked, “You started it!”

Frisk stuck their tongue out. Did not!

“Did too!”

They huffed in mock indignation. How dare he, they were always a perfect example of decorum, just not in that many big words, thank you very much.

Sam muttered something that sounded awfully like “liar” and got an elbow in the ribs for his troubles.

Somehow, they reached Frisk's appointed destination without getting into another playful scuffle. It was an old apartment building, and not a pretty one either. But it seemed sturdy if weathered. Frisk waltzed right through the front door which was unlocked for whatever reason, and Sam followed after only a moment of hesitation.

Three flights of stairs and only a few teasing comments about his lacking athleticism later, Frisk skipped along a carpeted hallway until they stopped at a specific door that really wasn't much unlike the other doors around it.

Aside from the colorful Christmas lights, that is.

Sam stared at the door in awe and wonder. “But it's July...” he muttered, and Frisk tittered. Oh that didn't matter! It's not like these were  _actually Christmas lights._ They were just... lights!

He gave them a doubtful look, “They  _are_ Christmas lights.”

Frisk shook their head. Nuh-uh, they weren't!

Sam looked ready to retort but Frisk gave the... interestingly decorated door two sharp knocks and he suddenly remembered why they were here in the first place. He started fiddling with his sleeves and stared up at the peephole as they waited for an answer.

Finally he heard some shuffling on the other side which stopped right at the door. Oh no he was getting nervous. He side-eyed Frisk to reassure himself. Alright, okay, they'd open the door any moment now and then he'd know who-

“who's there?” a low voice came to the door and he stopped in his tracks. Wait what?

Frisk snarked out a response with a shit-eating grin (not that either of them would use such wording,  _of course_ not, they were  _good_ kids) and after a moment the voice replied with a clear air of amusement, “lettuce who?”

Let us in! Frisk giggled and a deeply appreciative chuckle came from the other side before the door opened, revealing.... a skeleton. A short, sloppy one at that. Sam blinked, wow monsters really did come in all shapes and sizes.

The skeleton raised an eye.... ridge? “'us', huh? that your friend?” he asked, gesturing towards Sam, who smiled shyly as Frisk nodded with great enthusiasm. He huffed, “now, why would you bring her here?”

Sam's smile froze at the same time as Frisk's did. Ah, with them there to distract him, he'd forgotten about the- about the-

About the  _dress_ .

The skeleton's permanent smile lessened a bit at the tense atmosphere and Frisk sent both of them an apologetic look before addressing Sans because yes there  _was_ a reason they were here and their friend was called Sam and  _he_ kinda maybe possibly needed a place to stay for a little while? Pretty please?

Sans' eye sockets widened a fraction ( _how??_ ) and he gave Sam a rueful look. “sorry kid. won't happen again. and about staying, uh...” he seemed to think something over, “hmm, maybe come in first?”

Frisk let themself in without trouble, almost shoving him out of the way on their way in, much to Sans' exasperated amusement. Really, Frisk felt way too at home in all their friends' places. He turned his gaze to the other kid offering a lazy grin. “heya, 'm sans the skeleton. wanna come in?”

Sam snapped out of it, shy smile making a slightly strained comeback, “Sure thanks, uh, sir?”

That startled a snort out of Sans, which quickly devolved into full blown laughter. Sam stared in bafflement and turned to Frisk for some sort of explanation, but to his dismay they were laughing too. Traitor!

“aw, kid.” Sans finally managed to huff out between leftover chuckles, wiping a.... was that... yep, that was an actual blue tear. What. “you don't have to call me anything. sans is just fine.”

“How about bonehead...” Sam muttered in equal parts spite and embarrassment the way only a preteen could. When he looked up, however, Sans' eyes were almost glittering with contained mirth and he realized what he'd just said with an almost disbelieving huff of laughter. “Oh fine, whatever.” he said, cheeks red, and finally managed to enter the apartment proper.

The skeleton gave another chuckle behind him as he closed the door and followed the children to the nearby seating arrangement, sitting on the sole armchair while they took the sofa.

“so what's this about needing to stay somewhere?” he prompted, and while his posture and grin were relaxed as always, something about him seemed tense.

Sam looked down, fiddling with his sleeves, so Frisk tried to explain that, well, his mom's place wasn't really the.... best place for him right now and they really just wanted to get him away, at least for a night.

Sans took a good long look at the both of them, lingering somewhat on the skirt of the dress with a mild frown, before somehow sagging even more and sighing, a hand coming up to scratch nervously at his cheek... cheekbone?

“well... i'm not sure kids. wouldn't your mom, uh, _notice_?” the question was asked in Sam's direction and he answered without thinking.

“She wouldn't really care much...” He winced. Uh, oops.

Sans' brow furrowed ( _how????!!_ ) and he closed his eyes for a few moments. When he opened them again his expression was relaxed as usual. “welp,” he popped the p, “guess that's settled then. i'm sure paps will love having a guest over.”

Frisk cheered and promptly leaped out of their seat and straight into Sans. “oof! careful kid, handle with care. i'm fragile wares.” His tone was stern but his fond grin completely ruined the impression and Sam found himself smiling despite himself.

“Um, thanks. For- for letting me stay... and all...” he stumbled over his attempt at gratitude, much to Sans' amusement.

“that's alright kid. not like it's a problem for us or anything. but, uh...” he raised an eyeridge in consternation, removing a pouting Frisk from his personal space. “you kids got any plans for _after_ tonight?”

The children looked at each other, perplexed.

“Ummmm.” Sam responded rather eloquently.

Sans seemed wholly amused and entirely unimpressed.

 


	2. Tearful Hugs Are Totally A Part Of Sleepovers

“uh-huh, yeah it's no problem, nah don't worry mrs. darren, sam can borrow some of sandra's clothes, oh uh-” Sans blinked, perplexed, and removed the phone from the side of his skull to stare at it. “...she hung up on me.”

Sam winced at his mother's usual curtness, not for the first time wishing she wasn't quite so businesslike in every aspect of her life. “Sorry.”

Sans took a look at him and sighed, somewhat disgruntled, turning to speak to Frisk, “i'd say you owe me 'cause you know i hate phonecalls but, uh, that was pretty damn short so... one sleepover with an imaginary classmate all set up and ready to go.” he addressed the last part to Sam with an mischievous smirk, which Frisk returned with full enthusiasm in Sam's stead.

For his part, the boy opted for a grateful smile. “Thanks again for letting me stay the night, Mr. Sans.”

Sans seemed to choke on something between a laugh and a protesting remark, scratching at his cheekbone sheepishly, “i told ya, kid, you don't gotta call me that, i really prefer just sans.”

Sam's smile widened a smidgen, “Alright then, Mr. Just Sans.” he replied with a look of perfected innocent obliviousness that couldn't possibly be anything but faked. Sans narrowed his eyes for a moment before he started chuckling.

“not bad, kid.”

Any further further conversation was halted by the sound of the front door opening as well as–

“SANS, IM HOME! I HOPE TO DEAR STARS THAT YOU FINALLY PICKED UP THAT SOCK!”

–that.

Sam watched bewildered as another skeleton entered the apartment, just about bursting with energy and _volume_. He was busying himself at the entrance, setting down a bag and an umbrella

“OH, I MADE A LITTLE HUMAN FRIEND TODAY! I THINK I'LL BRING HER SOME OF MY SPAGHETTI– OH? ”

“hey bro. frisk brought a friend over, his name's sam. do you mind if he stays overnight?” Sans asked, although it was mostly a formality since he knew exactly how his brother would react to such a request.

“WELL OF COURSE!! GUESTS ARE ALWAYS WELCOME, _ESPECIALLY_ ANY FRIEND OF A FRIEND. HELLO HUMAN, I AM THE GREAT PAPYRUS! IT'S NICE TO MEET YOU.” he grinned broadly at Sam, “YOU'LL BOTH BE STAYING FOR DINNER, THEN?”

Sam hesitantly nodded, but stopped when he saw Frisk shake their head. They would've loved to stay, but their mom would be expecting them for dinner. Papyrus nodded in understanding and only a little disappointment.

Meanwhile the situation was starting to really dawn on Sam. It felt like water, a sea, endless and up too his chin, just ready to rise. Frisk would have to leave soon. And then he'd be alone, staying overnight with two strange adults, monsters even. This was a terrible idea, why had he even agreed to–

He felt a bony hand on his shoulder, “LITTLE HUMAN, ARE YOU ALRIGHT?”

Sam looked up into twin, very concerned sockets and couldn't help but compare them to Sans'. They were much smaller, the lights in them tiny and invisible at a distance, but they also seemed much more expressive, radiating worry and confusion.

“I... sorry, I'm just... nervous- worried? I'm- I don't know...”

“WHAT DO YOU HAVE TO BE WORRIED ABOUT?”

“I... I...” his fists clenched, bunching up the ugly, nauseating _dress_ and when he looked up there was nothing but sincere concern in those weirdly expressive eyesockets and the overwhelming feeling that had been building up since this morning, a sea of worries (his mom, the dress, the looks, the impromptu takeoff with Frisk, the strangers, a night away), suddenly retreated from his chin.

It gathered.

It crested.

_It fell_ .

There were tears in his eyes, on his cheeks, on his chin and the world became blurry as his legs felt like they would never hold him anymore. Through gradually increasing sobs he barely noticed the two pairs of arms around him, distinctly different in feel and size.

He wasn't really sure how long he spent sobbing his soul out, but by the time he calmed down he realized he'd been gripping Papyrus' shirt while he crouched on the ground, leaving the poor, very tall skeleton in what looked like a rather awkward sitting position to try and accommodate him.

Sam's face flushed with embarrassment and a fair bit of shame. “Oh god no, I'm so sorry Mr. Papyrus, I... I can't...” he felt almost on he verge of tears once again, this was just great.

“THERE'S NO NEED TO BE SORRY, LITTLE ONE. YOU OBVIOUSLY HAD SOMETHING TO CRY ABOUT, SO IT'S GOOD THAT YOU DID.”

Sam looked up, ignoring the ache induced by the movement, “But- but you're a total stranger and I don't- I shouldn't- I'm not even a  _little kid_ anymore–!”

“WE'RE NOT STRANGERS.” Papyrus cut in, though not unkindly, tilting his head with a smile, “YOU KNOW MY NAME AND I KNOW YOURS. BESIDES THERE'S NO SHAME IN CRYING, NO MATTER HOW OLD YOU ARE. RIGHT, SANS?”

“right bro.” came sans' voice from somewhere behind him.

And Sam simply took a moment to  _marvel_ at the sheer, sincere wonder that was Papyrus. He looked down, cheeks still a little pink and muttered an almost inaudible “Okay.”

It was after the tall skeleton stood up and headed to the kitchen with his brother, though not before smiling at Sam one last time and patting his head, that he realized that Frisk's arms were still wrapped around him from behind. A small smile tugged at his lips as he gently placed a hand on top of theirs.

“...I think you've been dethroned, Frisk.”

Their arms tightened around him in askance.

“I think Papyrus is the nicest person I've ever met.”

He could feel Frisk's shoulders shake as they giggled in delight.

 

**Notes for the Chapter:**

> well that escalated quickly  
> oops


	3. What The Heckitty Heck Is Privacy In The Face Of Freedom, Really?

“-and that's about what i know.” Sans finished explaining, his tone just the slightest bit strained.

Papyrus took a deep breath, preemptively getting his voice under control so it wouldn't carry outside the kitchen and to the human children in their living room. He turned to look at the adjacent wall, as if just staring hard enough would let him see the kids on the other side.

“WELL,” he began in a measured tone, “I BELIEVE WE NEED A MORE LONG TERM SOLUTION.”

Sans rubbed a hand down his face, bones grating against each other. “yeah paps, that's true. i just... don't know...”

He looked up as Papyrus clapped his hands and turned to the cupboards, “WELL, NO USE WORRYING ABOUT IT RIGHT NOW, WE CAN JUST TALK IT OUT WITH HIM AFTER DINNER. WHICH I SHOULD REALLY START MAKING.” he remarked as he pulled out pots and pans to set on the stove with practiced ease. “GO GIVE THE HUMANS SOME COMPANY IN THE MEANTIME, WOULD YOU BROTHER?”

“sure paps.” Sans answered with a fond smile, already walking out the open doorway, though not so fast that he didn't notice the chilled ball of dough being pulled out of the fridge. Ohhh, it seemed Sam was in for a treat.

In the living room, he found the kids smiling and talking.

“Thanks Frisk.” Sam said abashedly.

Frisk shook their head. It really was no problem! They were happy to help in any way.

“you kids plotting over there?” Sans interjected with an air of amusement and just the slightest hint of curiosity.

Sam startled slightly but Frisk simply raised an eyebrow, long since used to Sans' sneakiness. Really, they were getting much too sassy lately.

“It's really nothing, Mr. Sans-”

Nothing against _him_ at least.

“Frisk!”

If there was any plotting going on, then it would be behind his mom's back.

“ _Frisk!_ ”

Frisk tittered and Sans chuckled right along before giving them a curious look. Frisk tilted their head, it wasn't anything amazing, they'd just agreed to bring Sam some clothes tomorrow that he could change into for school.

Sans frowned and took a slow look at the boy, “speaking of which, i think we still have a box lying around full of my bro's babybones clothes, if you'd like to change into something... more comfortable.” he offered, pointedly not looking straight at Sam's current attire. “he was a pretty _big-boned_ kid so they should fit alright.”

Frisk snorted. Sans' sense of alright was what other people called impractically oversized.

“i take offense to that. clothes this comfy are definitely good for something. they make it harder for people to get _under my skin._ ” he grinned.

Yet another raised eyebrow. Soon enough they'd be a fully fledged teenager, he hoped Toriel was ready, even as he grinnedwider. “they're also pretty good for napping if i do say so myself.”

And another snort. He really shouldn't let Papyrus hear him say that.

Sans huffed half in amusement and half in acknowledgment, looking at the clock on the wall. “welp, it's getting late kiddo. better run home before tori assumes you've been kid _napped_ and put in a _rib_ cage _.”_ Despite his joking tone, both of them knew better than to dismiss such a claim. An overprotective Toriel was already intense enough, but being exhausted and stressed on top of that... yeah, they'd better get going.

They turned to hug Sam goodbye and gave him a reassuring smile. After quickly popping their head into the kitchen to wave goodbye to Papyrus, Frisk finally exited the apartment and headed home.

Finding himself alone with the skeleton, Sam fidgeted awkwardly for a moment. “Um, uh, about the clothes, that'd be, uh, nice.”

Sans' smile widened good-naturedly as he led the way to their spare room, hearing Sam follow hesitantly, “It's just over here.” The boxes with their old stuff and paraphernalia were usually kept in the closet of the guest room, since they had no other use for it.

After opening a few boxes to take a look at their contents, he finally found the right one and started rummaging until he fished out a simple orange-and-yellow striped shirt and a pair of loose, light shorts, handing them over to Sam before turning to the box and sticking it back in the closet. Sam had apparently seen an opportunity and taken it, since he had the shorts mostly on and was already pulling the shirt over his chest by the time Sans turned around. He was panting slightly and his hair was suddenly a wild mess mess of blond strands. The dress lay discarded on the floor.

Sans suppressed a laugh, barely, “Uh, glad that you seem to like the clothes, but maybe take your time and change in private next time. You know, without the risk of someone turning around at any moment.”

Sam flushed in embarrassment, “Ah, sorry. I just- I just wanted-” he directed a pointed look at the crumpled dress and muttered “I just wanted it off.”

Sans found himself ruffling the kid's hair into an even bigger mess as he passed him by, “That's alright, kiddo.”

“DINNER'S READY!” they heard a call from the kitchen. The skeleton motioned towards the kitchen and Sam followed, trying very hard to make his cheeks glow even a little less. He still couldn't quite believe he'd just done that, he was sure his cheeks were going to melt right off, though maybe they'd have the decency to wait until he'd hidden himself away from the world forever. What a nice thought.

All embarrassment, however, was forgotten once he awkwardly sat down with the brothers to eat.

“welp, _bone_ appetite.”

“SANS!”

He never knew ravioli could taste so good.

 

**Notes for the Chapter:**

> eyyyyyy come talk to me on tumblr, its the same username pretty much everywhere. also credit to the great punmaster Pilocene for punreading this chapter, without her sans just wouldnt be sans


End file.
